JP3954925B2 - Throwaway insert - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a throw-away insert used for a blade-tip-replaceable tool used for forming an end face including a weld bead portion of an electric resistance welded tube.
[0002]
[Prior art]
The throw-away tool used for machining including the bead part of the welded part such as an electric resistance welded tube, especially the tool used for machining the part where the shape of the cut surface of the work material is uneven is the bite. Due to the instability of time, chipping and chipping are likely to occur. As an example of pipe end face processing, for example, in Japanese Patent Application Laid-Open No. 2001-322002, an outer end portion of the steel pipe is attached to the bite holder that is detachably attached to the tool post in a Kaisaki chamfering device. There is an example in which an outer surface tip for chamfering and an inner surface tip for chamfering the inner end of the steel pipe are detachably mounted.
[0003]
[Problems to be solved by the invention]
However, when performing end-to-end machining including the bead part of the welded part of the ERW pipe with a blade-replaceable tool, the part that is damaged by the cutting edge has a higher probability of being generated at the part where the bead part is processed. There are challenges. An object of the present invention is to provide a blade-tip-replaceable insert having a strong blade edge strength at the cutting edge portion corresponding to the state of the surface to be cut corresponding to the total die machining.
[0004]
[Means for Solving the Problems]
In order to achieve the above object, in a throw-away insert with a replaceable blade edge used for total die machining of an end face including a weld bead portion of an electric resistance welded tube, the insert has a rectangular plate-like three corner portion as it is and another corner. The part is provided with a substantially 1/4 circular arc-inclined side surface and a linearly inclined side surface continuous with the angle α and angle β, and negative honing is applied to the cutting edge portion formed by crossing these with the upper surface of the insert. The throw-away insert is characterized in that it is provided on the linear cutting edge portions that are continuous at an angle α so that honing is expanded as the distance from the arc-shaped cutting edge portion increases.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the accompanying drawings. The accompanying drawings show an embodiment of an insert according to the present invention. The throw-away insert 1 of the present invention example shown in FIG. 1 uses a rectangular plate-shaped three corner portion as it is, and the other one corner portion has a substantially quarter-circular arc-inclined side surface that is a total shape. Are provided with a linear inclined side surface continuous at an angle α and an angle β. When set as a tool, when carrying out the total machining of the end face of the pipe, the substantially circular arc-shaped part becomes a rounded chamfer on the pipe outer diameter side, and the outer diameter part of the pipe is machined at an angle α. The straight cutting edge corresponds to the machining of the pipe end face side with the straight cutting edge of angle β.
[0006]
The intersections between these arc-shaped and straight side surfaces and the upper surface 2 become the cutting edges 3, 4, and 5. The cutting edges 3 to 5 have a width of 0.2 to 0.30 mm and an angle of negative honing. 20-30 degrees. Next, in order to cut the outer diameter part of the pipe, the linear cutting edge part 3 connected at an angle α is provided with a honing width that gradually increases as the distance from the arcuate cutting edge part 6 increases. The honing width of the linear cutting edge portions 3 continuous at the angle α is constant on the arcuate side, the honing width is 0.15 to 0.30 mm, the angle is 20 to 30 degrees, and negative honing is provided. On the edge side of the insert, that is, the cutting edge that cuts the outer diameter portion of the pipe, the width of the negative honing is gradually enlarged, and the honing width is 0.2 to 0.40, and the angle is 20 to 35 degrees. Expand one or both of the width and angle.
[0007]
The reason for expanding the honing width and angle is that the arc-shaped cutting edge is actually cut in the initial stage of end face processing. As cutting progresses, the actual cutting edge becomes longer, and the linear cutting edge portion 5 connected at an angle β is in the radial direction of the pipe, so it becomes a steady load. The cutting edge contact length of the portion 3 becomes longer as the processing proceeds, and the bead portion is always cut at the contact position between the cutting edge portion 3 and the pipe outer diameter. Next, when the cutting edge 5 becomes steady cutting, the cutting load also increases, the fluctuation of the cutting load increases at the bead portion having the unevenness of the shape of the surface to be cut, and the bead portion of the cutting edge 3 is cut. Chipping and chipping of the cutting edge are likely to occur. Further, since the honing width of the arcuate cutting edge 4 and the linear cutting edge portion 5 connected at an angle β is a constant cutting load, the honing width and the angle are provided small so as not to increase the cutting resistance. The linear cutting edge portion 3 that is continuously connected to each other is a portion that always cuts the weld bead portion, in particular, when the cutting edge that is actually cut becomes longer, the cutting edge portion that cuts the weld bead increases the honing width. Therefore, chipping and chipping of the cutting edge can be prevented. Therefore, the length 6 of the linear cutting edge portion that widens the honing width is about ½ to ¼ of the entire length of the linear cutting edge portion continuous at the angle α, thereby preventing chipping and the like. It becomes an insert.
[0008]
The insert shown in FIG. 1 was made of cemented carbide JIS, K10 equivalent grade, and was used by coating a TiAlN film. A cutting test was carried out in a state in which the end face of the ERW pipe was processed with a bead attached to a part of the outer diameter part of the pipe. As a comparative example, an example in which the honing of the cutting edge 3 was constant was also tested. The entire shape of the end face of the ERW pipe is processed, and in the example of the present invention, the straight cutting edge portion 3 connected at the angle α at which the outer diameter portion of the pipe is cut is not damaged, chipping and chipping of the cutting edge are reduced, and the service life is reduced. Thus, the surface roughness of the cut surface was maintained at a predetermined level. Moreover, in the comparative example, since the honing width of the linear cutting edge portions 3 continuous at the angle α was not widened, chipping occurred, and a larger chipping occurred than the chipping portion, resulting in a lifetime.
[0009]
【The invention's effect】
By applying the present invention, it is an insert used for forming a pipe end surface including a weld bead portion, and by providing the cutting blade honing for cutting the weld bead portion so as to gradually expand, without increasing the cutting load. , Chipping and chipping of the cutting edge were reduced, and the life could be extended significantly.
[Brief description of the drawings]
FIG. 1 shows a front view of a throw-away insert of an example of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Throwaway insert 2 Insert upper surface 3 Cutting edge 4 which the crossing part of the substantially circular arc-inclined side surface 2 and the upper surface 5 makes | forms The cutting edge 5 which the crossing part of the linear inclined side surface 3 and the upper surface 5 which continues at angle (alpha) forms Cutting edge 6 formed by the intersection of the linear inclined side surface 4 and the upper surface 5 connected at an angle β Length of the linear cutting edge portion that widens the honing width Angle of the cutting edge that processes the pipe outer diameter side β Pipe end surface is processed Cutting edge angle

Claims (4)

In the throw-away insert with a replaceable blade tip used for the total machining of the end face including the weld bead part of the ERW pipe, the insert has a rectangular plate-like three corner part as it is, and the other one corner part has a substantially quarter circle shape. Are provided with a linearly inclined side surface that is continuous at an angle α and an angle β, and a negative cutting is applied to the cutting edge portion formed by crossing these and the upper surface of the insert, thereby forming a linearly continuous surface at an angle α. A throw-away insert, wherein the blade portion is provided so as to expand honing as it moves away from the arcuate cutting blade portion. The throw-away insert according to claim 1, wherein the honing width of the linear cutting edge portion continuous at the angle α is constant on the arcuate side, and the honing width is gradually increased on the side of the insert. Throw away insert featuring The throwaway insert according to claim 2, wherein a cutting edge length for gradually expanding the width of the honing is set to ½ to ¼ of a total length of the linear cutting edge portions continuous at an angle α. Throw away insert. 5. The throwaway insert according to claim 1, wherein the honing has a width of 0.15 to 0.4 mm and an angle of 15 to 30 degrees in a negative range.

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